Bone regeneration study by new bioactive composite material——Bone marrow stem cells combining with porous tricalcium phosphate

By combining the enrichment technique of autologous bone marrow mesenchymal stem cells (MSCs)  and the rapid hybrid technique with porous β-tricalcium phosphate (β-TCP)，the bioactive composite (MSCs/β-TCP) was constructed. And with randomization and control principles，the enriched MSCs/β-TCP was identified for its osteogenesis function in goat spinal fusion experiment with the control of β-TCP alone and the control of autograft. The change of the number of MSCs post-enrichment was estimated by counting the colony-forming units which express alkaline phosphatase (CFUs/ALP⁺). The early stage of cell-scaffold hybrid was observed by scanning electron microscope (SEM). By X-ray，CT scan and histologic analysis，the osteogenesis of three sorts of materials and their transformations in vivo were evaluated. The results show that the concentration of MSCs after enrichment technique increases about 3.9 times，and the MSCs adhere to the inside wall of porous β-TCP only with 2 h hybrid. X-ray identifies that the moderate density shadows can be found gradually in the fusion site of group MSCs/β-TCP and group autograft. CT scan shows the fusion rates of group MSCs/β-TCP and autograft were 92% and 100% respectively，which were higher than those of group β-TCP alone (58%). The undecalcified section confirms that the osteogenesis ability of bioactive composite (MSCs/β-TCP) can compare with autologous bone graft in goat spinal fusion，and is better than that of β-TCP alone.